The present invention relates to stretchable absorbent articles, desirably disposable absorbent articles, which have a stretchable outer cover and distinctive stretchable top surface that has zones of differential stretch. Absorbent articles such as diapers, training pants or incontinence garments provide a close, comfortable fit about the wearer and contain body exudates when such articles perform properly. In certain circumstances, it can be desirable for absorbent articles to be capable of being pulled up or down over the hips of the wearer to allow the wearer or caregiver to easily pull the article on and easily remove the article if it has not been soiled. For example, such absorbent articles can assist in the toilet training of children.
Many conventional absorbent articles have typically employed fasteners that attach the waist sections of the articles around a wearer as well as various configurations of waist elastics, leg elastics, elasticized liners, and elasticized outer covers. The fasteners and elastic components have been employed to help produce and maintain the fit of the articles about the body contours of the wearer that can lead to improved containment. Maintaining this fit as the wearer moves and changes body position has been particularly difficult. For example, articles such as diapers are typically applied while the wearer is in a prone position such that their torso is extended and their abdomen is sunken. As the wearer changes from the prone position to a sitting position, the wearer's torso compresses and their abdomen extends outwardly thereby exerting forces on the article. If the waistband of the article does not have enough “give”, such forces can cause the waistband to shift and can undesirably result in increased leakage.
In an attempt to provide a maintained fit during movement, some conventional absorbent articles have included an outer cover composed of elastomeric materials, such as elastomeric, stretch-bonded-laminate materials. Such materials have included a layer of meltblown elastomeric fibers that has been stretched and sandwiched between facing layers composed of polypropylene spunbond nonwoven materials. The meltblown layer has typically been pattern-bonded to the facing layers with thermal bonds, sonic bonds and/or adhesive bonds. Other conventional absorbent articles have included folded pleats in the outer cover. The pleats are arranged to expand open as the article absorbs liquids.
Moreover, in an attempt to improve the containment of exudates many absorbent articles incorporate containment components on the interior of the article. For example, the containment components may consist of containment flaps that are disposed toward the side edges of the article and extend generally in the longitudinal direction of the article. In addition, flaps or pockets may be included in the absorbent article to contain exudates from migrating in the lateral direction and leaking out of the article. Other absorbent articles have integrated the use of both longitudinal and lateral flaps on the interior surface of the product to further prevent the migration of exudates and improve the containment capabilities of the article.
However, many of such attempts to provide absorbent articles that provide the desired fit while maintaining containment have not been completely satisfactory. For example, absorbent articles having stretchable outer covers sometimes have not exhibited the desired resistance to leakage, as they have not readily expanded to provide void volume for the containment of fecal exudates. In addition, it has been found that in some instances, absorbent articles incorporating stretch characteristics can compromise components included in the article for containment purposes. As such, it is possible that the performance of the absorbent article can be impacted by the addition of stretchable materials, particularly in the area of containment. Specifically, in articles that combine stretchable components, such as a stretchable outer cover and an extensible bodyside liner, with containment components, the stretchable components may render the containment components less effective upon insult.
Specifically, when the absorbent core swells upon the intake of an insult, the stretchable bodyside liner may allow the absorbent to expand into the void volume that is to be created by the containment components, such as containment flaps. This difficulty can be enhanced in situations where the stretchable outer cover does not elongate as readily as the stretchable bodyside liner. Thus, when the absorbent body is allowed to expand into the area between the containment flaps, they become less effective, and possibly ineffective for containing subsequent insults or soiling.
Accordingly, despite the attempts to develop improved absorbent articles, there remains a need for absorbent articles that can provide improved fit and resistance to leakage without excessive irritation to the skin of the wearer. Moreover, in some circumstances, there remains a need that such absorbent articles provide the benefits of conventional training pants and conventional diapers. That is, there remains a need for stretchable absorbent articles that conform to the wearer for enhanced fit and comfort, and effectively maintain void volume for improved levels of containment.